Sociosexual Behavior and Chemical Communication of Aotus nancymaae

Abstract

Owl monkeys (Aotus spp.) are unique because they are the only nocturnal anthropoids. Though medical researchers have used them extensively, thorough descriptions of their social behavior are sparse. We examined in detail the social behavior of 12 male-female captive pairs of Aotus nancymaae over an entire year. We compared data from males and females to determine if there are sexual differences in scent-marking, allogrooming, and other sociosexual behavior. We compared observation periods with and without mounting to determine if any behavior is associated with mounting. We present previously unreported behaviors for Aotus including urine-drinking and a suite of behaviors that we consider to function in olfactory communication. Males and females differed in their rates of several sociosexual behaviors; males anogenitally sniffed, drank urine, touched, and marked their mates more frequently than females did. We confirm earlier suggestions that allogrooming is rare in Aotus and is associated with mounting. Pairs of owl monkeys did not regularly exhibit behaviors that are typical for most monogamous primates but instead displayed a unique suite of behaviors adapted for their nocturnal lifestyle.

Hormonal Monitoring of Reproductive Status in Monogamous Wild Female Owl Monkeys (Aotus azarai) of the Argentinean Chaco

“…pregnant, cycling) of wild A. azarai females. Owl monkeys do not show any visual signs of ovarian cycling [Bonney et al, 1979[Bonney et al, , 1980Wolovich and Evans, 2007], therefore it is necessary to rely on changes in hormone levels to ascertain their reproductive status. To our knowledge, this is the first report of a characterization of female reproductive cycles from a free-ranging population.…”

Allogrooming in Male-Female Pairs of Captive Owl Monkeys (Aotus nancymaae)

“…They briefly tug and pull the pelage with an entire hand or mouth [Wolovich and Evans, 2007]. This behavior is quite different from the typical combing behavior associated with allogrooming in many primates.…”

“…Infants are groomed by adult males and females equally, and will be occasionally groomed by older juveniles (A. azarae [Rotundo et al, 2005]). Allogrooming in male-female pairs is less frequent [Robinson et al, 1987] (Aotus nancymaae [Wolovich and Evans, 2007]) and may be associated with mating behavior [Moynihan, 1964;Wolovich and Evans, 2007]. Wolovich and Evans [2007] did not determine whether there is greater male or female investment in partner grooming or whether partner grooming is reciprocal.…”

“…In nocturnal owl monkeys (Aotus spp. ), however, allogrooming in male-female monogamous pairs is reported to be infrequent and typically associated with mating [Moynihan, 1964;Wolovich and Evans, 2007]. Furthermore, owl monkey grooming is described as rough with frequent biting and tugging of the hair [Welker et al, 1998;Wolovich and Evans, 2007].…”

“…), however, allogrooming in male-female monogamous pairs is reported to be infrequent and typically associated with mating [Moynihan, 1964;Wolovich and Evans, 2007]. Furthermore, owl monkey grooming is described as rough with frequent biting and tugging of the hair [Welker et al, 1998;Wolovich and Evans, 2007]. More recent observations of owl monkey behavior suggest that the rate of grooming has likely been underestimated [Evans, 2013], prompting us to reevaluate comprehensively the details of allogrooming in Aotus by examining its mechanics and frequency.…”